Systems or devices for aiding in the collection of urine specimen are widely employed. In the simplest and widely used form for a urine collection system a patient voids a sample in an open cup either directly or through a suitable funnel. The urine analysis sample is then taken from the cup and any remainder discarded with the cup. This approach often requires transfer to a more permanent container such as a centrifuge specimen tube for more convenient transport or for laboratory analysis. Manual handling of the filled cup may result in undesirable spillage, contamination of the urine specimen and can be of concern both to the nurse for having to handle a wetted cup or embarassment to the patient for being unable to present a clean sample.
In a more advanced urine collection system, a disposable specimen tube is employed in the urine collection process. Typically, such tubes have small openings and are limited in size to contain a sample, say from eight to twelve milliliters. These tubes are particularly adapted for direct use in centrifuge machines for urine analysis. In view of the small openings of such specimen tubes, it is still necessary for the patient to void first into a larger container such as a cup and then pour some of the cup contents into a specimen tube. The tube may then be capped, labeled and sent to a laboratory for analysis. The latter urine transfer often is accompanied by some spillage and particularly wetting of the tube outer surface.
The reliance upon a small, disposable collection cup introduces potential contamination problems for so-called "mid-stream" urine collection. It is generally recognized that the initial urine stream is likely to include bacterial and other contaminating components from the urinary tract. This is particularly so for females. Since such contaminants distort the analytical picture one can draw of the urine condition in the bladder, systems have been proposed to obtain urine specimen from the middle of the stream where the level of contaminants is substantially lower.
Available mid-stream collection devices take a wide variety of forms. For example, in one commercially available mid-stream collector, sterile cup and closures are provided. A person is instructed to interrupt voiding and then restart and take a sample which is voided in the cup. Though this procedure is acceptable for obtaining a mid-stream sample, it does not appear wholly free from contamination problems such as may occur from patient handling of the collection cup. As a result, current generally employed mid-stream collection procedures and devices represent a compromise in the purity of the sample. A device or technique which enhances the purity of the mid-stream sample by eliminating a potential source of contamination is highly desirable.
One technique for collecting a mid-stream urine sample from females is described in the U.S. Pat. to Gleason et al No. 3,750,647. As described, a mid-stream sample is taken by allowing the later and stronger voiding stream to enter a different exit port and container from that for the earlier and weaker voiding stream. Automatic mid-stream collection is claimed by use of such device.
The Gleason et al apparatus is specially shaped to adapt to the female urinary tract and relies upon the patient's control in positioning of the device to achieve the desired stream separation. As one well known in the art of urine collection devices can appreciate, the Gleason device is not likely to be free from contamination problems. The early voiding stream for example may impinge upon intermediate surfaces causing splashing. Such splashings from the early stream are likely to contaminate the mid-stream sample anyway. Furthermore, the Gleason device is particularly complex and does not appear to be conveniently usable for mid-stream collections from males.
Another urine specimen collector is described in the U.S. Pat. No. 3,635,091 to Linzer et al. This collector is designed specifically to automatically obtain a mid-stream specimen. The device includes an outer enclosure and a collapsible inner bag releasably connected to the main opening of the outer enclosure. The initial voiding stream is collected in the inner bag which pulls away from the main opening after a certain amount of urine has entered the bag. Therefore, the initial stream is trapped in the inner bag and a mid-stream sample is obtained from the outer enclosure. The collector on the whole, however, is bulky, complex and appears unlikely to avoid contamination of the specimen from the initial stream.
Other urine specimen collection devices can be found in the art such as the collapsible, disposable funnel structure described in U.S. Pat. No. 3,572,318 to T. N. Garland, or the double tube container in U.S. Pat. No. 3,859,671 to M. Pomasello. An overflow handle connected to a urine collection container is described in the U.S. Pat. No. 3,033,222 to F. X. Connolly. The U.S. Pat. to Beach, No. 3,923,040 discloses a specimen collector particularly adapted to fill a centrifuge tube.